Ok for everybody…first create an empty project, open it and then custom your ui interface whatever you want then close it. Now the trick is to go inside your project folder in Saved / Config / Windows / and open and copy every thing inside EditorLayout.ini. then go inside your engine folder in Engine / Config / and paste and save everything you just copy in BaseEditorLayout.ini. Now everytime you create a new project will open your custom ui. Hope this is useful…just leave a comment if it works or if you have questions.